Calculating lots based on SL distance & % risk

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Hi

I have a function that calculates lots for opening positions. But it seems to be buying to many lots. I can't seem to find the problem with my logic.

Any help would be appreciated.

double calcLots(double slDist, double riskPercentage){   //Calculate amount of lots to buy/sell based on SL distance and percentage of account balance

   double risk = AccountInfoDouble(ACCOUNT_BALANCE) * riskPercentage / 100;   //$$$ lost if SL is triggerd
   double ticksize = SymbolInfoDouble(_Symbol,SYMBOL_TRADE_TICK_SIZE);
   double tickvalue = SymbolInfoDouble(_Symbol,SYMBOL_TRADE_TICK_VALUE);      //$$$ lost\won per tick
   double lotstep = SymbolInfoDouble(_Symbol,SYMBOL_VOLUME_STEP);
   
   if(slDist > 0 && ticksize > 0 && tickvalue > 0 && lotstep > 0){
      double moneyPerLotstep = slDist / ticksize * tickvalue * lotstep;
      double lots = MathFloor(risk / moneyPerLotstep) * lotstep;
      
      lots = MathMin(lots,SymbolInfoDouble(_Symbol,SYMBOL_VOLUME_MAX));
      lots = MathMax(lots,SymbolInfoDouble(_Symbol,SYMBOL_VOLUME_MIN));
      
      return lots;
   }else return 0;
}
 

the tick value is already per pip, so you calculate it like this:


double calcLots(double slDist, double riskPercentage){ 

   double risk = AccountInfoDouble(ACCOUNT_MARGIN_FREE) * riskPercentage / 100;  
   double tickvalue = SymbolInfoDouble(_Symbol, SYMBOL_TRADE_TICK_VALUE);   
   double lotstep = SymbolInfoDouble(_Symbol, SYMBOL_VOLUME_STEP);
   
   if(slDist > 0 && tickvalue > 0 && lotstep > 0){

      double moneyPerLot = slDist * tickvalue;

      double lots = risk / moneyPerLot;
      
      // ensure the lot size is formatted correctly with the lot step
      lots = MathFloor(lots / lotstep) * lotstep;
      
      lots = MathMin(lots, SymbolInfoDouble(_Symbol, SYMBOL_VOLUME_MAX));
      lots = MathMax(lots, SymbolInfoDouble(_Symbol, SYMBOL_VOLUME_MIN));
      
      return lots;
   }else{
      return 0;
   }
}


and don't base the lot on Account Balance, it's more proper to base it on the free margin available

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